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Galvanic vestibular stimulation (GVS) helps stabilize subjects when balance and posture are compromised. This work aimed to define the cortical regions that GVS activates in normal subjects. We used functional near-infrared spectroscopy (fNIRS) to test the hypothesis that GVS activates similar cortical areas as a passive movement. We used transcranial current stimulation (cathode in the right mastoid process and anode in the FPz frontopolar point) of bipolar direct current (2 mA), false GVS (sham), vibration (neutral stimulus), and back and forth motion (positive control of vestibular movement) in 18 clinically healthy volunteers. Seventy-two brain scans were performed, applying a crossover-type experimental design. We measured the heart rate, blood pressure, body temperature, head capacitance, and resistance before and after the experiment. The haemodynamic changes of the cerebral cortex were recorded with an arrangement of 26 channels in four regions to perform an ROI-level analysis. The back-and-forth motion produced the most significant oxygenated haemoglobin (HbO2 ) increase. The response was similar for the GVS stimulus on the anterior and posterior parietal and right temporal regions. Sham and vibrational conditions did not produce significant changes ROI-wise. The results indicate that GVS produces a cortical activation coherent with displacement percept.

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AIMS: In this study, we will describe a comprehensive haemodynamic analysis and its relationship to the dilation of the aorta in transposition of the great artery (TGA) patients post-arterial switch operation (ASO) and controls using 4D-flow magnetic resonance imaging (MRI) data. METHODS AND RESULTS: Using 4D-flow MRI data of 14 TGA young patients and 8 age-matched normal controls obtained with 1.5 T GE-MR scanner, we evaluate 3D maps of 15 different haemodynamics parameters in six regions; three of them in the aortic root and three of them in the ascending aorta (anterior-left, -right, and posterior for both cases) to find its relationship with the aortic arch curvature and root dilation. Differences between controls and patients were evaluated using Mann-Whitney U test, and the relationship with the curvature was accessed by unpaired t-test. For statistical significance, we consider a P-value of 0.05. The aortic arch curvature was significantly different between patients 46.238 ± 5.581 m-1 and controls 41.066 ± 5.323 m-1. Haemodynamic parameters as wall shear stress circumferential (WSS-C), and eccentricity (ECC), were significantly different between TGA patients and controls in both the root and ascending aorta regions. The distribution of forces along the ascending aorta is highly inhomogeneous in TGA patients. We found that the backward velocity (B-VEL), WSS-C, velocity angle (VEL-A), regurgitation fraction (RF), and ECC are highly correlated with the aortic arch curvature and root dilatation. CONCLUSION: We have identified six potential biomarkers (B-VEL, WSS-C, VEL-A, RF, and ECC), which may be helpful for follow-up evaluation and early prediction of aortic root dilatation in this patient population.

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The hemodynamic instability in the pregnant patient is a challenge for the treating team, due to the physiological peculiarities of her condition and the emotional impact of her care. Considering the increase in the mortality of pregnant women worldwide in developed countries due to múltiple factors associated with an inadequate level of care, anesthesiologists have an essential role within this team. Early recognition and timely treatment of a pregnant or postpartum patient is required. The evaluation of the hemodynamic status only with the clinic in changing situations may be insufficient in the obstetric patient for an adequate management, especially in pathophysiological conditions and with the impact of the pharmacological action of anesthesia. Therefore, monitoring at the patient's bedside, mainly through monitoring of cardiac output (CO), myocardial response and volemia status with minimally invasive cardiac output monitors, cardiac and pulmonary ultrasound evaluation allow a management that has an impact on survival.

La inestabilidad hemodinámica en la paciente gestante constituye un desafío para el equipo tratante, por las peculiaridades fisiológicas que ofrece su condición y por el impacto emocional que genera su atención. Considerando el aumento de la mortalidad de la embarazada a nivel mundial en países desarrollados debido a factores múltiples asociados a un nivel de cuidados no adecuados, es que los anestesiólogos cumplen un rol fundamental dentro de este equipo. Se requiere la detección precoz y tratamiento oportuno de una paciente gestante o puérpera. La evaluación del estado hemodinámico solo con la clínica en situaciones cambiantes puede ser insuficiente en la paciente obstétrica para un adecuado enfrentamiento, especialmente en condiciones fisiopatológicas y con impacto de la acción farmacológica de la anestesia. Es por esto que la monitorización al lado del paciente, principalmente a través de la vigilancia del gasto cardíaco (GC); la respuesta miocárdica y el estado de la volemia con monitores de gasto cardíaco mínimamente invasivos; la evaluación ecográfica cardíaca y pulmonar permiten un enfrentamiento que impacta en la sobrevida.

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Non-invasive assessment of central arterial pulse wave augmentation has been proved to be useful in predicting cardiovascular adverse events. Previous studies have shown that pre-pubescent girls had greater central augmentation pressure compared with height-matched boys. This study sought to investigate which factors contribute to the body height-independent sexual differences in central arterial wave reflection observed in childhood. This cross-sectional study involved 819 children and adolescents (6-18 years of age) of both sexes. Phenotypes of central haemodynamic were obtained by radial applanation tonometry. Heart rate corrected augmentation index (Aix@75) was greater in girls compared with boys (2.9 ± 10.7 vs -1.7 ± 12.9%, P < .001) as well as the central augmented pressure (cAP; 1.3 ± 3.3 vs 0.1 ± 3.8 mm Hg, P < .001), even adjusting for age, heart rate and body height. Left ventricular ejection duration (ED) was longer (320 ± 26 vs 314 ± 24 ms, P = .004) and time to inflection point (Tr) was shorter in girls (139 ± 14 vs 141 ± 21 ms, P = .014). The reduction of Aix@75 with increasing body height was steeper in boys (-0.499 ± 0.030 vs -0.428 ± 0.036%/cm, P < .001) as well as the reduction of cAP with increasing body height (-0.108 ± 0.010 vs -0.066 ± 0.013 mm Hg/cm, P < .001). Body height-independent sexual differences observed in the pulse wave reflection indices from early adolescence were mediated by different timing of forward and reflected pressure waves.

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PURPOSE: This study aimed to compare haemodynamic, rating of perceived exertion and blood lactate responses during resistance exercise with blood flow restriction (BFR) compared with traditional high-intensity resistance exercise in hypertensive older women. METHODS: Eighteen hypertensive women (age = 67·0 ± 1·7 years.) undertook three random sessions: (i) three sets; 10 repetitions; 20% of one repetition maximum (1RM) with BFR; (ii) three sets; 10 repetitions; 65% of 1RM; without BFR; and (iii) no-exercise with BFR. The exercise sessions were performed on knee extension equipment. RESULTS: Systolic (SBP) and diastolic blood pressure (DBP), heart rate (HR), stroke volume (SV) and cardiac output (CO) were significantly higher (P<0·05) in all sets of exercise sessions than the control. No statistically significant differences were detected between exercise sessions. However, SBP, DBP and systemic vascular resistance were higher (P<0·05) and SV and CO were lower (P<0·05) during the rest intervals in the session with BFR. The perceived exertion was significantly higher (P<0·01) in the 1st (4·8 ± 0·4 versus 3·1 ± 0·3), 2nd (7·3 ± 0·4 versus 5·7 ± 0·4) and 3rd sets (8·6 ± 0·5 versus 7·5 ± 0·4) of the traditional high-intensity resistance exercise compared with the exercise with BFR. Blood lactate was higher (P<0·05) in the traditional high-intensity resistance exercise (6·2 ± 0·7 mmol) than in the exercise with BFR (4·5 ± 0·4 mmol). CONCLUSION: In comparison with high-intensity resistance exercise, low-intensity resistance exercise with BFR can elicit: (i) same haemodynamic values during exercise; (ii) lower rating of perceived exertion; (iii) lower blood lactate; (iv) higher haemodynamic demand during the rest intervals.

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BACKGROUND: We compared intraocular pressure changes following laryngoscopy and intubation with conventional Macintosh blade and Airtraq optical laryngoscope. METHODS: Ninety adult patients were randomly assigned to study group or control group. Study group (n = 45) - Airtraq laryngoscope was used for laryngoscopy. Control group (n = 45) - conventional Macintosh laryngoscope was used for laryngoscopy. Preoperative baseline intraocular pressure was measured with Schiotz tonometer. Laryngoscopy was done as per group protocol. Intraocular pressure and haemodynamic parameters were recorded just before insertion of the device and subsequently three times at an interval of one minute after insertion of the device. RESULTS: Patient characteristics, baseline haemodynamic parameters and baseline intraocular pressure were comparable in the two groups. Following insertion of the endotracheal tube with Macintosh laryngoscope, there was statistically significant rise in heart rate and intraocular pressure compared to Airtraq group. There was no significant change in MAP. Eight patients in Macintosh group had tongue-lip-dental trauma during intubation, while only 2 patients received upper airway trauma in Airtraq group. CONCLUSION: We conclude that Airtraq laryngoscope in comparison to Macintosh laryngoscope results in significantly fewer rises in intraocular pressure and clinically less marked increase in haemodynamic response to laryngoscopy and intubation.

JUSTIFICATIVA: Comparar as alterações de pressão intraocular após laringoscopia e intubação com lâmina Macintosh convencional e laringoscópio óptico Airtraq. MÉTODOS: Noventa pacientes adultos foram randomicamente designados para os grupos estudo ou controle. No grupo estudo (n = 45) o laringoscópio Airtraq foi usado para laringoscopia e no grupo controle (n = 45) o laringoscópio Macintosh convencional foi usado para laringoscopia. A pressão intraocular foi mensurada no pré-operatório com tonômetro Schiotz. A laringoscopia foi feita de acordo com o protocolo de cada grupo. Pressão intraocular e parâmetros hemodinâmicos foram registrados logo antes da inserção do dispositivo e três vezes após a inserção do dispositivo, com intervalo de um minuto. RESULTADOS: As características dos pacientes, os parâmetros hemodinâmicos basais e a PIO basal foram comparáveis nos dois grupos. Após a inserção do tubo endotraqueal com o laringoscópio Macintosh, houve um aumento estatisticamente significativo da frequência cardíaca e da pressão intraocular em comparação com o grupo Airtraq. Não houve alteração significativa da PAM. Oito pacientes do grupo Macintosh sofreram trauma de língua-lábio-dental durante a intubação, enquanto apenas dois pacientes sofreram trauma das vias aéreas superiores no grupo Airtraq. CONCLUSÃO: Concluímos que o laringoscópio Airtraq, em comparação com o laringoscópio Macintosh, resultou em elevações significativamente menores da PIO e em aumentos clinicamente menos acentuados da resposta hemodinâmica à laringoscopia e intubação.

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BACKGROUND: We compared intraocular pressure changes following laryngoscopy and intubation with conventional Macintosh blade and Airtraq optical laryngoscope. METHODS: Ninety adult patients were randomly assigned to study group or control group. Study group (n=45) - Airtraq laryngoscope was used for laryngoscopy. Control group (n=45) - conventional Macintosh laryngoscope was used for laryngoscopy. Preoperative baseline intraocular pressure was measured with Schiotz tonometer. Laryngoscopy was done as per group protocol. Intraocular pressure and haemodynamic parameters were recorded just before insertion of the device and subsequently three times at an interval of one minute after insertion of the device. RESULTS: Patient characteristics, baseline haemodynamic parameters and baseline intraocular pressure were comparable in the two groups. Following insertion of the endotracheal tube with Macintosh laryngoscope, there was statistically significant rise in heart rate and intraocular pressure compared to Airtraq group. There was no significant change in MAP. Eight patients in Macintosh group had tongue-lip-dental trauma during intubation, while only 2 patients received upper airway trauma in Airtraq group. CONCLUSION: We conclude that Airtraq laryngoscope in comparison to Macintosh laryngoscope results in significantly fewer rises in intraocular pressure and clinically less marked increase in haemodynamic response to laryngoscopy and intubation.

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BACKGROUND: We compared intraocular pressure changes following laryngoscopy and intubation with conventional Macintosh blade and Airtraq optical laryngoscope. METHODS: Ninety adult patients were randomly assigned to study group or control group. Study group (n=45) - Airtraq laryngoscope was used for laryngoscopy. Control group (n=45) - conventional Macintosh laryngoscope was used for laryngoscopy. Preoperative baseline intraocular pressure was measured with Schiotz tonometer. Laryngoscopy was done as per group protocol. Intraocular pressure and haemodynamic parameters were recorded just before insertion of the device and subsequently three times at an interval of one minute after insertion of the device. RESULTS: Patient characteristics, baseline haemodynamic parameters and baseline intraocular pressure were comparable in the two groups. Following insertion of the endotracheal tube with Macintosh laryngoscope, there was statistically significant rise in heart rate and intraocular pressure compared to Airtraq group. There was no significant change in MAP. Eight patients in Macintosh group had tongue-lip-dental trauma during intubation, while only 2 patients received upper airway trauma in Airtraq group. CONCLUSION: We conclude that Airtraq laryngoscope in comparison to Macintosh laryngoscope results in significantly fewer rises in intraocular pressure and clinically less marked increase in haemodynamic response to laryngoscopy and intubation.

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The aim of this study was to compare the acute effect of resistance exercise (RE) with and without blood flow restriction (BFR) on heart rate (HR), double product (DP), oxygen saturation (SpO2 ) and rating of perceived exertion (RPE). Twenty-four men (21·79 ± 3·21 years) performed three experimental protocols in a random order (crossover): (i) high-intensity RE at 80% of 1RM (HI), (ii) low-intensity RE at 20% of 1RM (LI) and (iii) low-intensity RE at 20% of 1RM combined with partial blood flow restriction (LI+BFR). HR, blood pressure, SpO2 and RPE were assessed. The data were analysed using repeated measures analysis of variance and the Wilcoxon test for RPE. The results indicated that all protocols significantly increased HR, both immediately postexercise and during the subsequent 60 min (P<0·05), and postexercise DP (P<0·05), but there were no differences between protocols. The protocols of LI and LI+BFR reduced postexercise SpO2 (P = 0·033, P = 0·007), and the LI+BFR protocol presented a perception of greater exertion in the lower limbs compared with HI (P = 0·022). We conclude that RE performed at low intensity combined with BFR seems to reduce the SpO2 after exercise and increase HR and DP while maintaining a perception of greater exertion on the lower limbs.

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The increase in acetylcholine yielded by pyridostigmine (PYR), an acetylcholinesterase inhibitor, was evaluated for its effect on the haemodynamic responses-mean arterial pressure (MAP) and heart rate (HR)-and their nycthemeral oscillation in mice before and one week after myocardial infarction (MI). Mice were anesthetized (isoflurane), and a telemetry transmitter was implanted into the carotid artery. After 5 days of recovery, the MAP and HR were recorded for 48 h (10 s every 10 min). Following this procedure, mice were submitted to surgery for sham or coronary artery ligation and received drinking water (VEHICLE) with or without PYR. Five days after surgery, the haemodynamic recordings were recommenced. Sham surgery combined with VEHICLE did not affect basal MAP and HR; nevertheless, these haemodynamic parameters were higher during the night, before and after surgery. MI combined with VEHICLE displayed decreased MAP and increased HR; these haemodynamic parameters were also higher during the night, before and after surgery. Sham surgery combined with PYR displayed similar results for MAP as sham combined with VEHICLE; however, PYR produced bradycardia. Nevertheless, MI combined with PYR exhibited no change in MAP and HR, but these haemodynamic parameters were also higher during the night, before and after surgery. Therefore, MI decreased MAP and increased HR, while PYR prevented these alterations. Neither MI nor PYR affected nycthemeral oscillations of MAP and HR. These findings indicate that the increase in acetylcholine yielded by PYR protected the haemodynamic alterations caused by MI in mice, without affecting the nycthemeral haemodynamic oscillations.

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OBJECTIVES: This study was conducted to determine the changes in blood pressure and the pulse rate of patients with controlled hypertension having dental extraction under local anaesthesia utilizing 2% lignocaine with adrenaline, and to evaluate whether these changes in blood pressure were are attributable to addition of adrenaline. METHODS: This prospective study was carried out in 33 consecutive hypertensive patients who presented at the exodontia clinic of the Department of Oral and Maxillofacial Surgery, Lagos University Teaching Hospital (LUTH), Idi-Araba, Lagos, from December 2004 to August 2005 for intra-alveolar tooth extraction. Patients were randomly allocated to two groups according to the type of anaesthetic solution employed. Group A had tooth extraction done under 2% lignocaine with 1:80 000 adrenaline while group B had tooth extraction done under 2% lignocaine without vasoconstrictor (plain lignocaine). One tooth was extracted from each patient. Blood pressure and pulse rate measurements were recorded in the waiting room before surgery, in the surgery after local anaesthetic injection, during tooth extraction and 15 minutes after tooth extraction. RESULTS: The sample consisted of 20 females and 13 males age range 24 to 75 years (mean ± SD = 50.1 ± 11.7 years). There was no statistically significant difference between the systolic and diastolic blood pressure and pulse rate in the two groups after administration oflocal anaesthesia. However, the highest alteration in parameters was observed during tooth extraction in the two groups. CONCLUSION: The haemodynamic changes induced by injecting 2% lignocaine with adrenaline in patients with controlled hypertension during tooth extraction is within normal range and is not different from that induced by 2% lignocaine without adrenaline. We consider it essential that all precautions to prevent inadvertent intravascular injection be undertaken by the care provider.

OBJETIVO: Este estudio fue dirigido para determinar los cambios en la tensión arterial y la tasa de pulso de pacientes con hipertensión controlada, a quienes se les realiza una extracción dental bajo las condiciones de la anestesia local, utilizando lidocaína al 2% con adrenalina, y evaluar si estos cambios en la tensión arterial eran atribuibles a la adición de adrenalina. MÉTODO: Este estudio prospectivo se llevó a cabo en 33 pacientes hipertensos consecutivos que acudieron a la clínica de exodoncia del Departamento de Cirugía Oral y Maxilofacial del Hospital Docente Universitario (LUTH), Idi-Araba, Lagos, desde diciembre 2004 a agosto 2005, para extracciones intra-alveolares. Los pacientes fueron colocados de forma aleatoria en dos grupos, según el tipo de solución anestésica empleada. Al grupo A se le realizó la extracción con lidocaína al 2% con 1:80 000 adrenalina, mientras que al grupo B se le realizó la extracción con lidocaína al 2% sin vasoconstrictor (lidocaína pura). A cada paciente se le extrajo una pieza. Mediciones de la presión arterial y el pulso fueron realizadas en el salón de espera antes dela cirugía, en la cirugía tras la inyección con la anestesia local, durante la extracción del diente, y 15 minutos después de la extracción. RESULTADOS: La muestra consistió en 20 hembras y 13 varones cuyo rango de edad fluctuó de 24 a 75 años (± SD media = 50.1 ± 11.7 años). No hubo diferencia estadísticamente significativa alguna entre la tensión arterial sistólica y la diastólica, ni con respecto a la tasa del pulso en los dos grupos luego de la administración de la anestesia local. Sin embargo, la alteración más alta de los parámetros se observó durante la extracción en los dos grupos. CONCLUSIÓN: Los cambios hemodinámicos inducidos por la inyección de lidocaína al 2% con adrenalina en los pacientes con hipertensión controlada durante la extracción, están dentro del rango normal y no son distintos de los inducidos mediante lidocaína al 2% sin adrenalina. Se considera fundamental que los profesionales de la salud tomen todas las precauciones para prevenir inyecciones intravasculares inadvertidas.

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Total intravenous anaesthesia (TIVA) with propofol and ketamine proved to be very satisfactory from a clinical point of view. This blind randomised controlled trial was designed to compare induction and maintenance of anaesthesia under continuous infusion of propofol-racemic ketamine (PRK) with that of propofol-S-ketamine (PSK) and evaluate their haemodynamic, metabolic and ventilatory effects. Seven female dogs undergoing ovariohysterectomy were involved in each group. Anaesthesia was induced: in Group PRK, with propofol (4.0mg kg-1) and racemic ketamine (2.0mg kg-1) intravenous (i.v.), followed by i.v. infusion of propofol (initial dose of 0.5mg kg-1 min-1) and racemic ketamine (0.2mg kg-1 min-1); in Group PSK, with propofol (4.0mg kg-1) and S-ketamine (1.0 mg kgÕ) i.v., followed by i.v. infusion of propofol (initial dose of 0.5mg kg-1 min-1) and S-ketamine (0.1mg kg-1 min-1). Parameters were assessed before anaesthesia and in 6 time points after induction. In both groups, heart rate increased significantly at all time points. There was a slight decrease in systemic blood pressure, cardiac output and cardiac index in both groups. The systolic index decrease significantly and intense respiratory depression was observed in all groups, making assisted ventilation necessary.

A anestesia total intra-venosa (TIVA) com propofol e quetamina proporciona um efeito muito satisfatório do ponto de vista clínico. Este estudo, cego e randomizado, comparou a indução e manutenção da anestesia com infusão contínua de propofolquetamina racêmica (PRK) e propofol-quetamina-S (PSK) em cães, e avaliou seus efeitos hemodinâmicos, metabólicos e ventilatórios. Foram avaliadas sete cadelas em cada grupo, submetidas à ovariohisterectomia. A anestesia foi induzida no Grupo PRK, com propofol (4.0mg kg-1) e cetamina (2.0mg kg-1) por via intravenosa (i.v.), seguida de infusão contínua de propofol (dose inicial de 0.5mg kg-1 min-1) e cetamina racêmica(0.2mg kg-1 min-1) i.v. No Grupo PSK, a indução anestésica foi com propofol (4.0mg kg-1) e cetamina-S (1.0 mg kg-1) i.v., seguida de infusão contínua de propofol (dose inicial de 0,5mg kg-1 min-1) e cetamina-S ( 0.1mg kg-1 min-1) i.v. Os parâmetros foram observados antes da anestesia e em seis momentos após a indução anestésica. Em ambos os grupos, a freqüência cardíaca elevouse significantemente em todos os momentos. Houve pequena redução na pressão arterial sistêmica, débito cardíaco e índice cardíaco. O índice sistólico apresentou redução significante e houve intensa depressão respiratória em ambos os grupos. A anestesia total intravenosa com a associação do propofol à cetamina racêmica ou à cetamina-S proporciona boa estabilidade hemodinâmica, entretanto, há intensa depressão respiratória, havendo necessidade de assistência ventilatória.

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OBJETIVOS: A bupivacaína racêmica tem sido o anestésico local de escolha nos bloqueios regionais pela qualidade e duração de sua anestesia. Sua cardiotoxicidade é motivo de preocupações, e pesquisas têm sido realizadas para encontrar drogas com menor impacto. Seu isômero levógiro, a levobupivacaína, seria menos cardiotóxico pela menor afinidade aos receptores dos canais de sódio do coração, e é uma opção. Em nosso país, uma apresentação contendo 75 por cento do isômero levógiro e 25 por cento do isômero dextrógiro, denominada mistura enantiomérica, está disponível. O objetivo deste estudo foi comparar as repercussões hemodinâmicas da injeção intravascular de uma dose tóxica destes dois agentes em suínos. MÉTODOS: Suínos da raça Large White foram anestesiados com tiopental, entubados e ventilados mecanicamente, sendo, em seguida, instalada monitorização hemodinâmica com pressão invasiva e cateter de Swan-Ganz numa artéria pulmonar. Após repouso de 30 minutos, os animais foram divididos aleatoriamente em dois grupos, e foi realizada em duplo-cego intoxicação com um dos agentes na dose de 4 mg/kg. Os resultados hemodinâmicos foram avaliados então a um minuto, aos cinco, 10, 15, 20 e 30 minutos. RESULTADOS: A mistura enantiomérica causou maiores repercussões hemodinâmicas do que a bupivacaína racêmica. Estes resultados se opõem aos encontrados em humanos com o isômero levógiro, mas estão de acordo com achados recentes em animais. Extrapolar resultados de animais para seres humanos requer cautela, e novas pesquisas são necessárias. CONCLUSÃO: Em suínos, a mistura enantiomérica mostrou-se mais tóxica do que a bupivacaína racêmica, quando grandes doses são injetadas por via endovenosa.

BACKGROUND: Racemic bupivacaine has been the local anaesthetic of choice in regional blocks due to quality and duration of anesthesia. However its cardiovascular toxicity has been a source of concern and research has been made for lesser impact drugs. One choice is its levogyre isomer, levobupivacaine, apparently less cardiotoxic due a lower affinity to the heart sodium channels. In Brazil, a drug containing 75 percent of levogyre isomer and 25 percent of dextrogyre isomer, called enantiomeric excess mixture, is available. This study intends to evaluate haemodynamic effects of the intravascular injection of a toxic dose of both agents in swine. METHODS: Large White pigs were anaesthetized with thiopental, intubated and placed on mechanical ventilation. Haemodynamic monitoring was performed with an invasive blood pressure and Swan-Ganz catheter on a pulmonary artery. After a 30 minute rest period, animals were randomly divided in two groups and the intoxication was performed on a double-blind method with 4 mg.kg-1 of one of the drugs. Haemodynamic parameters were then evaluated at 1, 5, 10, 15, 20 and 30 minutes. RESULTS: The enantiomeric excess mixture caused greater haemodynamic effects than the racemic bupivacaine. These results diverge from those found in humans with levogyre isomer but are similar to recent results reported in animals. Care should be taken when extrapolating data obtained in swine to humans and further research is necessary. CONCLUSION: When high doses are injected in swine, the enantiomeric excess mixture was more toxic than the racemic bupivacaine.

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Objetivos: Determinar cambios hemodinámicos, estructurales y funcionales de pacientes con resistencia insulínica y sin síndrome metabólico. Métodos: Se seleccionaron diez pacientes de ambos sexos con diagnóstico de resistencia insulínica. Diez pacientes sanos ajustados por edad, sexo e índice de masa corporal (IMC) constituyeron el grupo control. El IMC y la presión arterial fueron registrados. Los pacientes fueron sometidos a una prueba de tolerancia oral a la glucosa. El índice de HOMAIR fue utilizado para el cálculo de la resistencia insulínica (HOMAIR: valor ≥ 2,5). La concentración de norepinefrina plasmática (NE) se cuantifico por HPLC. Los parámetros hemodinámicos, estructurales y funcionales del corazón fueron evaluados mediante el ecocardiograma bidimensional, eco doppler pulsado y doppler pulsado tisular. Resultados: La glucemia, la insulina basal y post-carga y el HOMAIR fueron significativamente más altos en el grupo de pacientes. El índice cardiaco resultó significativamente más bajo en el grupo de pacientes. La concentración de NE se correlacionó en forma positiva y estadísticamente significativa con las concentraciones de insulina basal y post-carga. La presión arterial diastólica se correlacionó en forma negativa y estadísticamente significativa con la insulina post-carga solo en el grupo control. El volumen diastólico final del ventrículo izquierdo se correlacionó en forma positiva y estadísticamente significativa con la insulina y el HOMAIR en el grupo de pacientes pero no en el grupo control. Conclusiones: Los niveles de insulina plasmática podrían desempeñar un papel muy importante en la modulación de los niveles plasmáticos de NE en pacientes con resistencia insulínica. La sobreactivación del sistema nervioso simpático podría condicionar anormalidades en el volumen sistólico final y el índice cardiaco, los cuales constituirían los cambios hemodinámicos adaptativos precoces en pacientes con resistencia insulínica sin síndrome metabólico.

Objective: To determine the haemodynamic, structural and functional changes in insulin-resistant subjects Methods: Ten insulin-resistant subjects were studied. Asymptomatic subjects were studied as a control group. Blood pressure and body mass index were registered. Standard oral glucose tolerance test was performed. Plasma glucose and insulin were measured at baseline and 2 hours post glucose load. Insulin resistance index HOMAIR was calculated. Insulin resistance was considered if HOMAIR value was ≥ 2.5. Plasma norepinephrine (NE) was measured by HPLC. In order to examine the mass and cardiac function, bi-dimensional echocardiogram and imaging doppler tissue were performed. Results: Plasma glucose, insulin and HOMAIR were significantly higher in insulin-resistant subjects. There was no significant difference in plasma NE concentration between groups. The cardiac index was the only haemodynamic variable found to be significantly lowers in insulin resistant subjects. A significant positive correlation between NE with fasting and post load insulin concentration was observed. In control group, a significant negative correlation between diastolic blood pressure and post load insulin concentration was observed. The left ventricle systolic end-volume was positively and significantly correlated with insulin and HOMAIR in insulin-resistant subjects, but not in controls. Conclusions: Insulin levels may play role in modulating plasma NE levels, particularly in insulin-resistant subjects. The increased sympathetic activity in these subjects might lead to an abnormality in the left ventricle systolic end-volume and cardiac index, which might be the earlier adaptative haemodynamic changes due to cardiac post-load.

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Este estudo teve como objetivos identificar e analisar os aspectos que implicam na decisão em reprocessar e reutilizar cateteres de hemodinâmica originalmente para um único uso as condições gerais do seu reprocessamento. Os dados foram coletados em 13 instituições hospitalares do município de São Paulo que aceitaram participar da pesquisa e que realizavam procedimentos hemodinâmicos, por meio de entrevista com enfermeiros do setor de hemodinâmica e da Comissão de Controle de Infecção Hospitalar (CCIH). O instrumento utilizado para a coleta de dados foi de múltipla escolha abrangendo as diversas etapas do reprocessamento. Constatamos que a causa principal para decidir pela reutilização dos cateteres é o aspecto econômico, mas nem todos os enfermeiros concordavam com a reutilização. A responsabilidade na decisão pelo reprocessamento e reutilização desses cateteres não era conhecida ou estava diluída entre um único profissional (médico ou enfermeiro), exceto a CCIH em duas instituições. As etapas de execução dessa prática não ocorriam em um só setor, distribuindo-se principalmente entre o serviço de hemodinâmica e serviço terceirizado de esterilização. O enfermeiro da Central de Materiais e Esterilização não estava envolvido e esse setor participava de algumas das etapas do processo na minoria das instituições. Apesar de constatarmos que as mesmas utilizavam mecanismos de controle, a principal problemática foi identificada na diversidade das ações, com bases empíricas na maioria das vezes não correspondendo às recomendações encontradas em literatura científica. Tendo em vista que a prática de reprocessamento reutilização de artigos originalmente de uso único é uma realidade nacional e internacional, concluímos pela necessidade de mais pesquisas que forneçam subsídios cientificamente comprovados para sua qualificação, assim como um maior comprometimento das instituições, associações profissionais e órgãos governamentais

The main objective of this study was to identify and analyze which aspects would imply in taking the decision of reprocessing and reusing haemodynamic catheters originally designed for single use and general reprocessing conditions. The data were collected in 13 hospital entities in São Paulo district, which accepted to take part in the research, and used to realize haemodynamic procedures through interviews with Haemodynamic Section Nurses and Hospital Infection Control Committee (HICC). The instrument used for collecting data was multiple choices comprising the different steps of the reprocessing. We stated that the main reason for deciding for reusing the catheters is the savings aspect, although not all the nurses agreed with the reusing. The responsibility in deciding for reprocessing and reusng those catheters was unknown or had been dissolved in a single professional (doctor or a nurse), except the HICC in two entities. The steps in the accomplishment of that practice did not happen in a single section, being mainly shared between the haemodynamic service and thirth-party sterilization service. The Central Supply nurse was not involved, and that section used to take part in some of the steps of the process only in few entities. Although we stated that they used control mechanisms, the main difficulty was identified in the diversity of the actions, most of the times with empiric basis, and not corresponding to the recommendations retrieved in scientific literature. Having in mind that the reprocessing and reuse of devices originally designed for single use is a national and international reality, we came to the conclusion that more researches are necessary to provide scientifically certified endowments for its qualification, as well as a major commitment of the entities, professional associations and governamental organs

Assuntos